Let's break this down. We're going to add 277 and 2311 together.

Step 1: We'll start by adding the digits 7 & 1 in column 1 and get 8.

Step 2: We'll start by adding the digits 7 & 1 in column 2 and get 8.

Step 3: We'll start by adding the digits 2 & 3 in column 3 and get 5.

Step 4: We'll start by adding the digits 0 & 2 in column 4 and get 2.

So, 277 + 2311 = 2588.

